// 将其它数据转换为 number 值

// 将 Number 当作普通函数使用时，
// 用于将其它数据转换为 number 值(原始类型)

let x = Number();
console.log( x , typeof x );

x = Number( null );
console.log( x , typeof x );

x = Number( 0 );
console.log( x , typeof x );

x = Number( '' );
console.log( x , typeof x );

x = Number( false );
console.log( x , typeof x );

x = Number( [ ] );
console.log( x , typeof x );

x = Number( NaN );
console.log( x , typeof x );

x = Number( undefined );
console.log( x , typeof x );

x = Number( { } );
console.log( x , typeof x );